Currently, most viewing of three-dimensional (3D) image and video content is done using stereoscopic source image information viewed through so called “shutter glasses” of various types. In general, this means that the same source display (e.g., an LCD) displays right eye and left eye images in alternate succession over time. The use of shutter glasses enables the correct image to be viewed by the correct eye at the correct time to enable the illusion of 3D content.
However, one of the limitations of the technology is the length of time it takes various LCD pixels and systems to change state, either to generate new image frames or to adjust the shutter glasses. The “slow” response times of LCD pixels presents some challenges that have yet to be overcome.
During use a display is refreshed with the current data starting with data at the top and then working its way down to the bottom for each frame (in a process well known in the art as analogous to rater scanning). After each frame and a short vertical blanking period a new frame is presented in the same top to bottom manner.
However, in a stereoscopic display the alternate frames have left and right eye images. This fact results in some application difficulties. Because the time required for each pixel to change state can be a significant portion of the frame time, there is little or no time during a frame when all of the pixels are representative of one single frame. More commonly, each frame contains some of the previous frames data. Since in 3D viewing the stereoscopic data is presented in alternating left and right eye formats, this feature presents some limitations to the technology.
Due to this lag in frame data change there is typically little or no time during frame when all of the display pixels represent only one frame's image data. As a consequence there is little or no time during a frame when the shutter glasses can be “opened” to view either a left or right eye view. Accordingly, numerous artifacts and reductions in the quality of the image viewing experience are commonly encountered using this approach.
Accordingly, there is a need for approaches that avoid the aforementioned problem and provide improved image quality in an economic fashion. This disclosure addresses some of those needs.